📝 Documentation updates

src/simulator/error.rs

@@ -1,3 +1,19 @@
+//! # Error
+//! 
+//! This module contains the definition of the MachineError struct,
+//! for error management in the Machine module.
+//! 
+//! Basic usage:
+//! 
+//! ```
+//! fn example(x: bool) -> Result<(), MachineError> {
+//!     match x {
+//!         true => Ok(()),
+//!         _ => Err(MachineError::new("Machine failed because of ..."));
+//!     }   
+//! }
+//! ```
+
 use std::fmt;
 
 /// Machine Error